The work of Anna Oppermann (1940-93, Germany) is pioneering in the way it brings together ideas from process art, conceptual art, and the arte povera and performance art of the 1960s and 1970s. She composed variable assemblages of objects, texts, photographs, coloured photo-canvases and paintings, which she called ensembles. They interweave highly diverse, sometimes conflicting elements and express the artist's experience of the complexity of the world with all its contrasts.

Each ensemble arised from found objects, images and ideas which to the artist had become metaphors for the diversity, absurdity and contrasts of personal and public life. She described them as exercises in observation and insight that are in principal infinite.
Before her premature death, Oppermann developed more than 60 ensembles.